﻿/*
* Copyright (c) 2006-2007 Erin Catto http://www.gphysics.com
*
* This software is provided 'as-is', without any express or implied
* warranty.  In no event will the authors be held liable for any damages
* arising from the use of this software.
* Permission is granted to anyone to use this software for any purpose,
* including commercial applications, and to alter it and redistribute it
* freely, subject to the following restrictions:
* 1. The origin of this software must not be misrepresented; you must not
* claim that you wrote the original software. If you use this software
* in a product, an acknowledgment in the product documentation would be
* appreciated but is not required.
* 2. Altered source versions must be plainly marked as such, and must not be
* misrepresented as being the original software.
* 3. This notice may not be removed or altered from any source distribution.
*/

package Box2D.Dynamics{


import Box2D.Collision.*;
import Box2D.Collision.Shapes.*;
import Box2D.Dynamics.Contacts.*;
import Box2D.Dynamics.*;
import Box2D.Common.Math.*;
import Box2D.Common.*;


/// Implement this class to provide collision filtering. In other words, you can implement
/// this class if you want finer control over contact creation.
public class b2ContactFilter
{

   /// Return true if contact calculations should be performed between these two shapes.
   /// @warning for performance reasons this is only called when the AABBs begin to overlap.
   public virtual function ShouldCollide(shape1:b2Shape, shape2:b2Shape) : Boolean{
      var filter1:b2FilterData = shape1.GetFilterData();
      var filter2:b2FilterData = shape2.GetFilterData();
      
      if (filter1.groupIndex == filter2.groupIndex && filter1.groupIndex != 0)
      {
         return filter1.groupIndex > 0;
      }
      
      var collide:Boolean = (filter1.maskBits & filter2.categoryBits) != 0 && (filter1.categoryBits & filter2.maskBits) != 0;
      return collide;
   }
   
   static public var b2_defaultFilter:b2ContactFilter = new b2ContactFilter();
   
};

}
